Closure retaining mechanism



Dec. 19, 1933.

w. H. SMITH 1,940,027

CLOSURE RETAINING MECHANI SM Filed April '11, 1950 2 Sheets-Sheet 1 :ILU

INVENTOR. WALTERH. SMITH ATTORNEY.

Dec. 19, 1933. H MW 1,940,027

CLOSURE RETAI NING MECHANI SM l N VEN TOR.

WALTER H. SMITH A TTORNE Y.

Patented Dec. 19, 1933 UNITED- STATES PATENT oF'FicE 7 1,940,02 CLOSURE RETAINING MECHANISM Walter H. Smith, Philadelphia, Pa, assignor to The Electric Service Supplies Company, Philadelphia, Paz, a corporation of Pennsylvania Application April 11, 1930. Serial-No. 443,304 3 Claims. (01. 292 2oi') This invention relates to closure operating mechanisms and more particularly toimprovements in means for insuring the retention of a closure, such as a door or the like, in a given position under predeterminedly establishedconditions.

The loss of heat due to open doors and the like in steam and electric railway cars, locomoti'ves and motor vehicles has always proved to Y be expensive and has increased considerably the cost of operating such vehicles at the same time that it has made it difficult to maintain a suitable temperature for the convenience and comfort of the passengers. In my copending application, Serial No. 412,196, filed December 6, 1929, Letters Patent No. 1,804,443, granted May 12, 1931, I have disclosed a form of door holding and releasing apparatus including means operative to hold the vehicle door in openposition only when the vehicle was at rest or was coasting with power 01f, as when approaching a station. Immediately upon operation of the motor control for starting the electric railway type of car or upon operation of' the conductors' signalsystem employed to notify the engineer to start the steam railway type of car or train this door holding means was automatically rendered inoperative to maintain the door in open position, the door being then free to be moved into closed position through the action of any suitable door closing means, such as a door check or the like.

In said copending application the'apparatus comprised generally an electromagnet including an armature which was operatively associated with the door, the arrangement being such that during operation of the train under power'the electromagnet was deenergized whereby the door was permitted to move freely, under the action of the door closing means, into closedposition.

The present invention has for its primary objects, in addition to those-mentioned in said' copending application, certain improvements or variations in=the design and operation of the originally disclosed apparatus. One of these objects is to provide an electromagnetically controlled latch' adapted'to engage the edge ofthe door or likeclosure, theelectromagnet being energized to render the latch inoperative automatically as power is applied to start the train.

A further object of the present invention is the provision of an electromagnetically controlled latch which is operative to engage and retain the door or like closure in open position while the electromagnet is deenergized. It will be observed that the present invention difiers from that disclosed in my earlier filed copending application in that in the present arrangement the door is releasable from its open position only when the electromagnet is energized whereas in the former arrangement this result was attained only upon deenergization of the electromagnet'.

Other objects and advantages of the invention such as have to do with simplicity in construction, efficiency and certainty of operation ease of installation and durability in use, will be apparent from the following detailed description.

The invention consists substantially in the combination, construction, location and relative arrangement of parts, all as will be described more fully hereinafter, as shown in the accompanying drawings, and as finally pointed out in the appended claims. In the said accompanying drawings: 7

Figure 1 is a top plan view showing the'invention applied to a swingably mounted door, the closed position of the latter being represented by the dotted lines;

Figure 2 is a side elevational view showing the apparatus in operative position for maintainin the door in open position; 7

Figure 3 is a vertical sectional view taken on theline 3--3 of Figure 1;

Figure 4 is a top plan view showing a modie fied arrangement of the present invention; and

Figure 5 is a frontal elevational view of the arrangement shown in Figure 4.

Referring'now to the drawings, and more par ticularly to Figures 1 to 3 thereof, it will be observed that for purposes of illustration and explanation the present invention has been shown applied to a door 19, such as thedoor leading from the interior or" a railway passenger car to the vestibule or platform thereof. It will be understood that this door is hingedly mounted, as at 11, to the usual'jamb, the door being shown infull lines when in its open position and in broken lines when in its closed position. It will be further understood that the door is equipped with a suitable device, such as a pneumatically operated door closing device 12, which is operative and tends constantly to move the'door into its closed position. The present invention is concerned with the provision of a mechanism which is operative only under predeterminedly established conditions to retain the door in its open position against the action or influence of the door closing means 12.

Secured to the wall 13 to one side of the hinged edge of the door 10, preferably by means of the screws 14 or the like, is a bracket member 15. This bracket member, which is of substantially U-shape, supports an electromagnetically operated latch mechanism, designated generally by the reference numeral 16., The mechanism 16 may be secured to the bracket 15, by the screws 17 or the like, and essentially comprises an angle member 18 from the horizontally extending branch 19 of which depends an electromagnet core 20. This core 20, which is preferably threaded into engagement with the aforesaid branch 19 of the angle member, as at 21, is surrounded by the usual electromagnet coil 22.

Pivotally secured to the lower end of the ver tical branch 23 of the angle member bymeans of a pivot pin 24 is one end of a detent or latch member 25, the opposite and. free end of said member being provided with a downwardly presenting jog or extension 26 adapted to engage the outer end of a bracket 27 or similar elementsuitably secured to the door, said engagement being automatically effected when the door is swung into open position. A coiled spring 28 surrounding the pivot pin 24 normally tends to maintain the detent in depressed position for engagement with said outer free end of the bracket 27. The pivoted end of the detentmay be provided with a projection 29 which coacts with the lower end of the angle member 18 to limit the downward throw of the detent.

It will be understood of course that the detent constitutes the movable armature of the electromagnet, the arrangement being such that when said electromagnet coil 22 is energized the armature or detent 25 is drawn upwardly and out of engagement with the door bracket 2'7. The door is then free to move into its closed position under the action or influence of the door closing means 12.

In the modified arrangement shown in Figures 4 and 5 the electromagnetically controlled detent 25 is operative to directly engage or hook over the upper edge of the door 10, thereby dispensing with the door bracket element 27. It

will be evident that whereas in the former arrangement the detent moves in a vertical plane intersecting the wall 13, in the modified arrangement the detent moves in a vertical plane paralleling the wall. In said modified arrangement, the electromagnet device 16 .is secured to one branch 31 of an angle bracket 30, the other branch 32 of said bracket being secured, as by screws 33, to the Wall 13 immediately adjacent the hinged edge of the door and at an elevation sufiicient to permit the upper edge of the door to pass under and be engaged by the free end of the detent 25.

In order to protect the upper edge of the door against undue wear and to minimize the friction engendered as the detent rides over said upper edge, a metal shoe 34 or the like may be fitted upon the door. As in the case of Figures 1 to 3, the modified arrangement of Figures 4 and 5 also includes the provision of a suitable door closing means, such as the illustrated device 12.

It will be understood that in either of the herein described arrangements the electromag' net is, in the case of an electric railway car or train, connected or interlocked in circuit with the train. power control in such manner that when the motor control is operated to start the train or'car, the electromagnet is energized whereby to lift the detent out of position for holding the door open in consequence of which the door is free to move into its closed position under the action of the closing means 1.2. The same result may be effected in the case of a steam operated train by the simple expedient of including the electroinagnet in an electrical circuit which is completed automatically when the usual conductors signal cord is pulled as a signal to start the train. An arrangement for so controlling the electromagnetic circuit by operating the conductcrs signal cord is described in my copending application hereinbefore referred to, the sole difference between the arrangement therein described and that necessary in the present case being that in the former the electromagnetic circuitris interrupted whereas in the latter the circuit is completed when the signal cord is pulled.

Among the advantages of the arrangement herein described is the fact that no part of the door retaining mechanism is carried by the door 1 .rthcr observed that the said mechanism inclu ing the mounting bracket, the e'lectromagnet, the detent and all associated partsmay mounted as a unitary assembly in proximity to for coaction with the door the opening and closing of which it is desired to control. It will be understood of course that the invention her-einbeiore described and the application may be varied within wide limits and that various changes and modifications thereof may be made without departing from the genera principle or real spirit of the invention. It is accordingly intendedto claim the invention broadly, as well as specifically, as indicated in the appended claims.

What is claimed as new and useful is:

1, In combination with a movable closure, a bracket fixedly secured in position, an electromagnet supported by said bracket, a springpressed latch pivotally secured to said bracket and constituting an armature for said magnet, said latchbeing provided in its free end with means for retaining the closure in a given posi tion when said magnet is not energized, and coacting means in said bra et and latch for maintaining the latch in on to be freely engaged by the closure when the latter is moved into said given position, latch eing withdrawable from said closure engaging position upon energization of said magnet.

2. In a latch mechanism of the character described, a unitar embly of substantially U- shape, one leg of said assembly being in the form of a latch member movable relatively to the opposite stationary leg thereof, and an electromagnet arranged between the legs of said assembly and directly operative upon said movable latch member for withdrawing the latter into inoperative position upon energization of said electromagnet.

3. In a latch mechai'iism of the character described, a unitary assembly of substantially U- shape, one of said assembly being in the form of a latch member movable relatively to the opposite stationary leg thereof, and an electromagnet arranged between the legs of said assembly and directly operative upon said movable latch member for withdrawing the latter into inoperative position upon energization of said electromagnet, and spring means for maintaining said latch member in operative position while said electromagnet is deenergized.

WALTER H. SMITH.

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